Apparatuses for wind turbine blade railroad transportation and related systems and methods

ABSTRACT

A tip bolster (32) for supporting a wind turbine blade (40) on a railcar (14) includes a clamp (360) including first and second clamp arms (364, 366) having first and second jaws (384, 386), respectively, and being configured to be selectively movable relative to each other in a clamping direction for applying and releasing a clamping force on the blade (40) interposed therebetween, via the first and second jaws (384, 386), wherein the first and second clamp arms (364, 366) are configured to be urged relatively toward each other in response to a decrease in the clamping force.

TECHNICAL FIELD

This invention generally relates to wind turbines, and more particularlyto apparatuses, systems, and methods for transporting a wind turbineblade via railroad.

BACKGROUND

Wind turbines are used to produce electrical energy using a renewableresource and without combusting a fossil fuel. Generally, a wind turbineconverts kinetic energy from the wind into electrical power. Ahorizontal-axis wind turbine includes a tower, a nacelle located at theapex of the tower, and a rotor having a plurality of blades extendingfrom a hub and supported in the nacelle by means of a shaft. The shaftcouples the rotor either directly or indirectly with a generator, whichis housed inside the nacelle. Consequently, as wind forces the blades torotate, electrical energy is produced by the generator.

Transportation of wind turbine blades from their production site totheir installation location or to an interim storage site poses avariety of technical challenges, particularly in view of theever-increasing size of individual blades. For example, the lengths ofsome modern wind turbine blades may be in the vicinity of approximately250 feet (or approximately 80 m). It is often desirable or necessary totransport such blades via railroad. However, transportation of such longblades can present significant challenges for railroad transportation.For example, railroad profiles (e.g., side clearances) are typicallytightly limited and the trains must negotiate curved sections ofrailroad as well as complex and/or crowded rail yards. As a result, longblades often span across multiple railcars for improved maneuveringaround curves, junctions, or other potential railroad or railroad-sideobstructions.

In many cases, a train includes first and second railcars operativelycoupled to each other for hauling by a locomotive, and a root end of theblade is supported on the first railcar via a vertically pivotable rootbolster and a region of the blade near a tip end thereof is supported onthe second railcar via a vertically pivotable tip bolster. One or moreadditional railcars may be operatively coupled to the first and secondrailcars, such as between the first and second railcars. In any event,the blade may be supported by the root bolster at the root end and maybe supported by the tip bolster at a location along the blade spacedapart from the tip end.

In this regard, the tip bolster may be positioned somewhat inboard fromthe actual tip end of the blade (e.g., approximately one-quarter of theblade length therefrom) since the actual tip end of the blade may be toodelicate to adequately support the weight of the blade, while the rootbolster is typically positioned at the actual root end where thestrength of the blade is often relatively high. By supporting the tipend region and root end of the blade on the vertically pivotablebolsters on separate railcars, the blade may be able to “cut corners” asthe railcars travel along the railroad. In this regard, the blade maytypically overlie the train including the first and second railcars, aswell as any additional railcars therebetween, as the train traverses astraight section of the railroad such that the railcars arelongitudinally aligned with each other. However, as the train rounds acurved section of the railroad such that the railcars becomelongitudinally offset from each other, a middle region of the bladebetween the vertical pivot axes of the bolsters may extend outside thetrain's footprint on the inside of the curve to “bridge” over the spacealongside the train that is radially inward of the train. In some cases,the tip end of the blade may likewise extend outside the train'sfootprint on the outside of the curve to “swing out” over the spacealongside the train that is radially outward of the train.

Such prior art arrangements may not be suitable for transporting bladeshaving lengths greater than a particular threshold length via aparticular section of railroad. In this regard, the available clearancesalongside a railroad for accommodating a bridging middle region of ablade and for accommodating a swinging out tip end of a blade may bevery limited. For example, there may be insufficient available clearanceinside of the curve of a curved section of the railroad to accommodatethe middle region of a particularly long blade as the railcars round thecurved section. An obstruction may be located along the railroad on aradially inward side thereof which would impede the middle region of theblade from safely bridging radially inwardly of the train as therailcars travel along the railroad. More particularly, the middle regionof the blade could collide with such an obstruction, thereby damagingthe blade and potentially rendering the blade unusable. This problemtypically cannot be resolved by only adjusting the position of the tipbolster (and thus, of the associated vertical pivot axis) to allow thetip end of the blade to swing out farther radially outwardly of thetrain, since other obstructions may be located along the railroad on aradially outward side thereof which would similarly impede the tip endof the blade from safely swinging out farther as the railcars travelalong the railroad.

Many sections of railroad are provided with a predetermined sideclearance boundary along either side thereof. Such side clearanceboundaries are typically expressed as a horizontal distance from acenterline of the railroad, and may vary depending on variouscharacteristics of a particular section of railroad, such as a curvaturethereof. For example, a predetermined side clearance boundary of arailroad may be defined as a particular horizontal distance from thecenterline of the railroad and may be determined based on a radius oflateral curvature of the railroad (e.g., measured to the centerline ofthe railroad). Together, the side clearance boundaries may define ahorizontal operating envelope available for occupation by the trainincluding the railcars and any associated equipment and/or cargo carriedthereby.

In one example, a first curved section of railroad for facilitating a13° degree right turn of the train may have a radius of approximately442 feet (approx. 135 m) lateral curvature (e.g., measured to thecenterline of the railroad), a radially inward side clearance boundarydefined approximately 9 feet (approx. 2.5 m) from the centerline of therailroad, and a radially outward side clearance boundary definedapproximately 11 feet (approx. 3.5 m) from the centerline of therailroad to provide a horizontal operating envelope having a total widthof approximately 20 feet (approx. 6 m). In another example, a secondcurved section of railroad for facilitating a 13° degree left turn ofthe train may have a radius of approximately 442 feet (approx. 135 m)lateral curvature (e.g., measured to the centerline of the railroad), aradially inward side clearance boundary defined approximately 12 feet(approx. 4 m) from the centerline of the railroad, and a radiallyoutward side clearance boundary defined approximately 14 feet (approx.4.5 m) from the centerline of the railroad to provide a horizontaloperating envelope having a total width of approximately 26 feet(approx. 8 m).

Such first and second curved sections may be impassable for a windturbine blade having a length greater than a certain threshold lengthand carried by the train using the prior art arrangement describedabove. For example, a blade having a length of approximately 245 feet(approx. 75 m) would be incapable of remaining within the horizontaloperating envelopes of such curved sections using the prior artarrangement. In particular, the bridging middle region of the bladeand/or the swinging out tip end of the blade would protrude beyond theprovided side clearance boundaries and thus encounter potentialobstructions. Therefore, it may be difficult or impossible to transportblades of certain lengths via certain sections of railroad using suchprior art techniques.

Moreover, in some cases, the blade may be operatively coupled to therespective railcar(s) via a clamp positioned around a region (e.g., atip end region) of the blade. The clamp may frictionally engage theblade to restrain the blade on the railcar. Thus, acceleration of therailcar may be transmitted to the blade via the clamp. Likewise, brakingaction of the railcar may be transmitted to the blade via the clamp.However, the frictional engagement of the clamp with the blade may beundermined during transportation if the blade drifts or creeps forwardor backward relative to the clamp, which could ultimately result in theblade slipping free from the clamp. On the other hand, the clamp may beapplied excessively tightly around the blade in an effort to preventsuch slippage, which may inadvertently cause the clamp to compressivelydamage the blade thereby compromising the structural integrity of theblade and rendering the blade unusable. Moreover, the interface betweenthe blade and the clamp may be subjected to vibrations and shocks duringtransportation which may cause unexpected decreases in the clampingforce applied to the blade. Current clamping systems do not provide anymeans to account for these undesirable changes in the applied clampingforce.

Manufacturers of wind turbines and wind turbine components continuallystrive to improve systems and methods associated with the transportationand handling of wind turbine blades. It would therefore be desirable toprovide improved apparatuses, system, and methods for transporting awind turbine blade via railroad that accommodate maximized blade lengthsand ensure a sufficiently firm clamping action on the blade to restrainthe blade during transportation.

SUMMARY

In one embodiment, a tip bolster for supporting a wind turbine blade ona railcar includes a clamp including first and second clamp arms havingfirst and second jaws, respectively, and being configured to beselectively movable relative to each other in a clamping direction forapplying and releasing a clamping force on the blade interposedtherebetween, via the first and second jaws, wherein the first andsecond clamp arms are configured to be urged relatively toward eachother in response to a decrease in the clamping force. A decrease in theclamping force may alternatively be understood or expressed as a shiftin position of the clamped blade. The clamp may further include at leastone mechanical energy storage device configured to selectively store andrelease energy for urging at least one of the first and second clamparms relatively toward the other of the first and second clamp arms inresponse to the decrease in the clamping force. For example, the atleast one mechanical energy storage device may include at least onespring.

The clamp may include at least one guide rod extending parallel to theclamping direction, and the second clamp arm may be movable toward andaway from the first clamp arm along the at least one guide rod. In thisregard, the clamp may further include an actuator configured to effectmovement of the second clamp arm along the at least one guide rod. Forexample, the actuator may include a rotatable drive screw extendingparallel to the clamping direction and a drive plate including at leastone through-bore configured to slidably receive the at least one guiderod and a threaded bore configured to threadably receive the drivescrew, such that rotation of the drive screw effects movement of thedrive plate along the guide rods for urging the second clamp arm towardthe first clamp arm and for allowing the second clamp arm to be movedaway from the first clamp arm. The actuator may further include at leastone mechanical energy storage device positioned between the drive plateand the second clamp arm and configured to selectively store and releaseenergy between the drive plate and the second clamp arm for urging thesecond clamp arm toward the first clamp arm in response to the decreasein the clamping force. For example, the at least one mechanical energystorage device may include at least one spring. The at least one springmay be positioned about the at least one guide rod. In addition oralternatively, the at least one spring may be configured to bepre-loaded by the drive plate in response to continued movement of thedrive plate toward the first clamp arm after the second jaw presses theblade against the first jaw. In this regard, the at least one spring maybe configured to expand in response to the decrease in the clampingforce to urge the second clamp arm toward the first clamp arm.

The clamp may include at least one spring-loaded separator extendingbetween the first and second clamp arms for biasing the first and secondclamp arms relatively away from each other in the clamping direction. Inaddition or alternatively, the tip bolster may include a turntableconfigured to be pivotable relative to the railcar about a verticalaxis, wherein the clamp is supported by the turntable. The tip bolstermay include a carriage configured to be translatable along the railcarin a longitudinal direction thereof, wherein the clamp is supported bythe carriage. A transportation arrangement may include the tip bolsterpositioned on and pivotable relative to a first railcar about a firstvertical axis, a root bolster positioned on and pivotable relative to asecond railcar about a second vertical axis, and a blade pivotablysupported on the first railcar via the tip bolster and pivotablysupported on the second railcar via the root bolster.

In another embodiment, a method of transporting a wind turbine bladeincludes providing a railcar and a tip bolster mounted to the railcar,wherein the tip bolster includes a clamp having first and second clamparms having first and second jaws, respectively. The method alsoincludes interposing the blade between the first and second clamp armsand selectively moving the first and second clamp arms relatively towardeach other in a clamping direction for applying a clamping force on theblade via the first and second jaws. The method further includes urgingthe first and second clamp arms relatively toward each other in theclamping direction in response to a decrease in the clamping force.Urging the first and second clamp arms relatively toward each other mayinclude selectively releasing energy from at least one mechanical energystorage device to at least one of the first and second clamp arms inresponse to the decrease in the clamping force. For example, the atleast one mechanical energy storage device may include at least onespring. In this regard, selectively moving the first and second clamparms relatively toward each other may include pre-loading the at leastone spring. In addition or alternatively, the method may includereleasing the blade from the first and second jaws via at least onespring-loaded separator extending between the first and second clamparms for biasing the first and second clamp arms relatively away fromeach other in the clamping direction

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention and,together with a general description of the invention given above, andthe detailed description given below, serve to explain the invention.

FIG. 1 is a perspective view of a transportation arrangement including aplurality of railcars, a wind turbine blade, a root bolster, and a tipbolster in accordance with an aspect of the invention.

FIG. 2 is a top elevation view of the transportation arrangement of FIG.1 , showing the railcars traversing a straight section of railroad andlongitudinally aligned with each other, and the wind turbine bladeoverlying the train.

FIG. 3 is a top elevation view similar to FIG. 2 , showing the railcarsrounding a first curved section of railroad and longitudinally offsetfrom each other, the middle region of the wind turbine blade bridgingradially inwardly from the train, and the tip and root ends swingingradially outwardly from the train.

FIG. 4 is a top elevation view similar to FIG. 2 , showing the railcarsrounding a second curved section of railroad and longitudinally offsetfrom each other, the middle region of the wind turbine blade bridgingradially inwardly from the train, and the tip and root ends swingingradially outwardly from the train.

FIG. 5 is a front perspective view of the root bolster of FIG. 1pivotably mounted to a root fixture fixed to the bed of the respectiverailcar.

FIG. 5A is a partial disassembled front perspective view of the rootbolster of FIG. 5 , showing the lower turntable and upper cradle of theroot bolster exploded from the root fixture.

FIG. 5B is a partial disassembled rear perspective view of the rootbolster of FIG. 5 , showing the angle plate of the root bolster explodedfrom the lower turntable and upper cradle of the root bolster.

FIG. 5C is a partial disassembled front perspective view of the rootbolster of FIG. 5 , showing the rigid arm of the root bolster explodedfrom the upper cradle of the root bolster.

FIG. 6 is a front perspective view of the tip bolster of FIG. 1pivotably mounted to a tip fixture fixed to the bed of the respectiverailcar.

FIG. 6A is a partial disassembled front perspective view of the tipbolster of FIG. 6 , showing the lower carriage of the root bolster beingtranslatably mounted to the rails of the tip fixture.

FIG. 6B is a partial disassembled front perspective view of the tipbolster of FIG. 6 , showing the intermediate turntable and upper clampof the tip bolster exploded from the lower carriage of the tip bolster.

FIGS. 7A-7F are side elevation views of the root bolster illustrating amethod of loading the wind turbine blade onto the root bolster.

FIGS. 8A-8E are front elevation views of the tip bolster illustrating amethod of loading the wind turbine blade onto the tip bolster.

FIGS. 9A-9C are top elevation views of the tip bolster illustrating amethod of loading the wind turbine blade onto the tip bolster.

DETAILED DESCRIPTION

With reference to FIG. 1 , an exemplary transportation arrangement 10includes a train 12 including a plurality of railcars 14 operativelycoupled together for hauling by a locomotive along a railroad (notshown). The railcars 14 each have respective flat beds 16 and verticallypivotable trucks 18, and collectively define first and second sides 20,22 of the train 12. The transportation arrangement 10 also includesvertically pivotable root and tip bolsters 30, 32 positioned on separaterailcars 14, and a blade 40 supported by the root and tip bolsters 30,32 such that the blade spans across multiple (e.g., at least two)railcars 14. As described in greater detail below, the root and tipbolsters 30, 32 may each be positioned at inboard locations along theblade 40 such that the blade 40 may be capable of swinging laterallyoutwardly from the first and/or second sides 20, 22 of the train at bothends thereof as the railcars 14 round a curved section of the railroad,for example, thereby allowing the blade 40 to have an increased lengthas compared to those allowed by prior art transportation arrangements.The tip bolster 32 may also be configured to automatically adjust aclamping force applied to the blade 40 by a portion of the tip bolster32 in response to the applied clamping force falling below a desiredamount to maintain a sufficiently firm and substantially continuousclamping action on the blade 40 to restrain the blade 40 duringtransportation.

The blade 40 may be of any suitable configuration and may include, forexample, a root end 42, a tip end 44, a leading edge 46, a trailing edge48 (FIG. 7D), a pressure side 50, and a suction side 52 (FIG. 2 ). Asbest shown in FIG. 2 , the root end 42 and the tip end 44 of the blade40 are spaced apart by a length L of the blade 40. In one embodiment,the length L of the blade 40 may be between approximately 150 feet(approx. 46 m) and approximately 300 feet (approx. 91 m). For example,the length L of the blade 40 may be approximately 245 feet (approx. 75m). The leading edge 46 and the trailing edge 48 of the blade 40 arespaced apart by a chord which varies along the length L of the blade 40,and which is widest at a shoulder 54 of the blade 40. The illustratedblade 40 is outfitted with a root frame 56 rigidly coupled to the blade40 at the root end 42 and a tip frame 58 rigidly coupled to the blade 40between the shoulder 54 and the tip end 44 to provide lifting points forhoisting the blade 40, for example.

With continuing reference to FIG. 2 , the train 12 may be configured totraverse a straight section of the railroad wherein a centerline C ofthe railroad is straight such that the railcars 14 are longitudinallyaligned with each other. As a result, the blade 40 may be longitudinallyaligned with and overlie the train 12, including the railcars 14carrying the bolsters 30, 32 and any other railcars 14 therebetween. Inother words, the blade 40 and, more particularly, both the root and tipends 42, 44 thereof, may substantially lie within a horizontal footprintof the train 12 when viewed from above (although some relatively smallportions of the exterior surface of the blade 40 may extend slightlybeyond such a footprint, such as if a thickness of the blade 40 exceedsa width of one or more of the bed(s) 16 of the underlying railcar(s)14). In any event, the blade 40 is clearly safely within a horizontaloperating envelope defined between inner and outer side clearanceboundaries Bi, Bo of the straight section of the railroad.

As shown in FIGS. 2-4 , the blade 40 is pivotable relative to the bed 16of the railcar 14 carrying the root bolster 30 about a first verticalaxis V1 spaced apart from the root end 42 by a first distance D1 anddefined by the root bolster 30, and the blade 40 is pivotable relativeto the bed 16 of the railcar 14 carrying the tip bolster 32 about asecond vertical axis V2 spaced apart from the tip end 44 by a seconddistance D2 and defined by the tip bolster 32. In the embodiment shown,the first vertical axis V1 is positioned between the root end 42 and theshoulder 54 of the blade 40. In any event, a root region 60 of the blade40 may be defined between the root end 42 of the blade 40 and the firstvertical axis V1, a middle region 62 of the blade 40 may be definedbetween the first and second vertical axes V1, V2, and a tip region 64of the blade 40 may be defined between the tip end 44 of the blade 40and the second vertical axis V2.

In one embodiment, the first distance D1 may be equal to approximatelyone-tenth of the length L of the blade 40. For example, the firstdistance D1 may be between approximately 20 feet (approx. 6 m) andapproximately 40 feet (approx. 12 m). In the embodiment shown, the firstdistance D1 may be approximately 23 feet (approx. 7 m). In oneembodiment, the second distance D2 may be equal to approximatelyone-quarter of the length L of the blade 40. For example, the seconddistance D2 may be between approximately 50 feet (approx. 15 m) andapproximately 70 feet (approx. 21 m). In the embodiment shown, thesecond distance D2 may be approximately 56 feet (approx. 17 m). In oneembodiment, the root bolster 30 and/or tip bolster 32 may be positioneddirectly above the truck 18 of the corresponding railcar 14, such thatthe respective vertical axis V1, V2 may be substantially coaxial with avertical pivot axis of the underlying truck 18.

Thus, the root region 60 and the tip region 64 of the blade 40 may eachbe configured to extend laterally away from a radially outward side 20,22 of the train 12, and the middle region 62 of the blade 40 may beconfigured to extend laterally away from a radially inward side 20, 22of the train 12, when the railcars 14 carrying the bolsters 30, 32 arelongitudinally offset from each other.

In this regard, and with reference to FIG. 3 , the train 12 may beconfigured to round a first curved section of the railroad wherein thecenterline C of the railroad is curved such that the railcars 14 arelongitudinally offset from each other. For example, the first curvedsection may facilitate a 13° degree right turn of the train 12, and mayhave a radius of approximately 442 feet (approx. 135 m) lateralcurvature (e.g., measured to the centerline C), a radially inward sideclearance boundary Bi defined approximately 9 feet (approx. 2.5 m) fromthe centerline C of the railroad, and a radially outward side clearanceboundary Bo defined approximately 11 feet (approx. 3.5 m) from thecenterline C of the railroad to provide a horizontal operating envelopehaving a total width of approximately 20 feet (approx. 6 m). Bypositioning the root and tip bolsters 30, 32 and, thus, the respectivevertical axes V1, V2, inboard of the respective ends 42, 44 of the blade40, the middle region 62 of the blade 40 may bridge radially inwardlyfrom the second side 22 of the train 12 without protruding beyond theradially inward side clearance boundary Bi, while the root and tipregions 60, 64 may each swing radially outwardly from the first side 20of the train 12 without protruding beyond the radially outward sideclearance boundary Bo. In other words, at least portions of each of theroot region 60, middle region 62, and tip region 64 of the blade 40 mayextend outside of the horizontal footprint of the train 12 when viewedfrom above, but the entire blade 40 including the root region 60, themiddle region 62, and the tip region 64 may remain safely within thehorizontal operating envelope as the train 12 rounds the first curvedsection of the railroad.

With reference to FIG. 4 , the train 12 may be configured to round asecond curved section of the railroad wherein the centerline C of therailroad is curved such that the railcars 14 are longitudinally offsetfrom each other. For example, the second curved section may facilitate a13° degree left turn of the train 12 may have a radius of approximately442 feet (approx. 135 m) lateral curvature (e.g., measured to thecenterline C), a radially inward side clearance boundary Bi definedapproximately 12 feet (approx. 4 m) from the centerline C of therailroad, and a radially outward side clearance boundary Bo definedapproximately 14 feet (approx. 4.5 m) from the centerline C of therailroad to provide a horizontal operating envelope having a total widthof approximately 26 feet (approx. 8 m). By positioning the root and tipbolsters 30, 32 and, thus, the respective vertical axes V1, V2, inboardof the respective ends 42, 44 of the blade 40, the middle region 62 ofthe blade 40 may bridge radially inwardly from the first side 20 of thetrain 12 without protruding beyond the radially inward side clearanceboundary Bi, while the root and tip regions 60, 64 may each swingradially outwardly from the second side 22 of the train 12 withoutprotruding beyond the radially outward side clearance boundary Bo. Inother words, as with the first curved section of the railroad describedabove, at least portions of each of the root region 60, middle region62, and tip region 64 of the blade 40 may extend outside of thehorizontal footprint of the train 12 when viewed from above, but theentire blade 40 including the root region 60, the middle region 62, andthe tip region 64 may remain safely within the horizontal operatingenvelope as the train 12 rounds the second curved section of therailroad.

Therefore, the inboard positioning of the first and second vertical axesV1, V2, via the inboard positioning of the respective bolsters 30, 32,may allow the blade 40 to have a maximized length L which efficientlyutilizes the available side clearances along the railroad while ensuringthat the entire blade 40 avoids obstructions adjacent to the railroadbeyond the side clearance boundaries Bi, Bo.

Referring now primarily to FIGS. 5-5C, the illustrated root bolster 30is movably mounted to a root fixture 70 fixedly coupled to the bed 16 ofthe underlying railcar 14 against movement relative thereto. As bestshown in FIG. 5A, the root fixture 70 includes a base plate 72 and acentral shaft 74 extending generally upwardly from the base plate 72.The illustrated base plate 72 has a generally circular peripheralportion 76 and a generally X-shaped central portion 78 for providingrigidity to the base plate 72 and from which the central shaft 74extends. In one embodiment, the root fixture 70 may be welded to the bed16 of the railcar 14 along the edges of the X-shaped central portion 78to fixedly couple the root fixture 70 to the bed 16 of the railcar 14.Alternatively, the root fixture 70 may be fixedly coupled to the bed 16of the railcar 14 in any other suitable manner. In any event, thegenerally circular peripheral portion 76 defines an upper bearingsurface 80, the purpose of which is described below. In the embodimentshown, the shaft 74 includes a central bore 82 for rotatably receiving agenerally cylindrical spindle 84. As shown, the spindle 84 includes aplurality of threaded bores 86 for threadably receiving respectivefasteners 88. The illustrated root fixture 70 also includes a pluralityof hoist rings 90 positioned on an upper surface of the X-shaped centralportion 78 and configured to facilitate hoisting of the root fixture 70onto the bed 16 of the railcar 14 via a lifting arrangement (not shown),for example.

The illustrated root bolster 30 includes a lower turntable 100configured to be mounted to the root fixture 70 and pivotable relativethereto about the first vertical axis V1. As best shown in FIG. 5A, thelower turntable 100 has a generally I-shaped frame 102 and a centralsleeve 104 extending generally downwardly therefrom and configured torotatably receive the shaft 74 of the root fixture 70 such that theshaft 74 and the sleeve 104 may collectively define the first verticalaxis V1. In the embodiment shown, the lower turntable 100 includes acentral recess 106 in the frame 102 generally above and axially alignedwith the sleeve 104, and a raised boss 108 centered within the recess106 and including a plurality of through-bores 110 configured for axialalignment with the threaded bores 86 of the rotatable spindle 84 of theroot fixture 70 and for receiving the respective fasteners 88therethrough to secure the lower turntable 100 to the rotatable spindle84. As shown, a selectively removable cover 112 may be configured toenclose the recess 106 and conceal the fasteners 88 therein. In theembodiment shown, the lower turntable 100 also includes a plurality ofperipheral feet 114 extending generally downwardly from the frame 102and each having at least one lower bearing pad 116 configured to glidealong the circular bearing surface 80 of the root fixture 70 duringrotation of the lower turntable 100 relative thereto to assist insupporting the lower turntable 100 on the root fixture 70. Theillustrated lower turntable 100 also includes a pair of oppositelydisposed support heels 118 positioned on an upper surface of the frame102, and a pair of lower eyelets 120 (FIG. 5B) positioned on a centralside surface of the frame 102, the purposes of which are describedbelow. In the embodiment shown, a threaded shank 122 extends outwardlyfrom the outer side surface of at least one of the pair of lower eyelets120. The illustrated lower turntable 100 further includes a plurality ofhoist rings 124 positioned on an upper surface of the frame 102 andconfigured to facilitate hoisting of the lower turntable 100 onto theroot fixture 70 via a lifting arrangement (not shown), for example.

In the embodiment shown, the root bolster 30 also includes an uppercradle 130 coupled to the lower turntable 100 and fixed against rotationrelative to the lower turntable 100 about the first vertical axis V1such that the upper cradle 130 and lower turntable 100 are configured torotate thereabout together. In the embodiment shown, the upper cradle130 has a generally I-shaped frame 132 and a plurality of peripheralpivot blocks 134 extending generally upwardly therefrom. As shown, eachof the pivot blocks 134 pivotably supports a respective shackle 136, andeach shackle 136 pivotably supports a pair of saddles 138 configured toconfront the pressure side 50 or the suction side 52 of the blade 40 tobe supported by the root bolster 30 at or near the leading edge 46 ofthe blade 40. In the embodiment shown, the upper cradle 130 alsoincludes a plurality of springs 140 extending between the frame 132 andthe shackles 136 for absorbing and damping shock impulses, for example.Each of the saddles 138 includes at least one friction pad 142configured to frictionally engage the respective side 50, 52 of theblade 40. In this regard, the saddles 138 and/or friction pads 142 maybe sized and shaped to conform to the exterior surface of the blade 40.In one embodiment, the friction pads 142 may include a rubber material.The pivotability of the saddles 138 relative to the shackles 136 and ofthe shackles 136 relative to the pivot blocks 134 may allow the saddles138 to automatically adjust under the weight of the blade 40 to conformto the exterior surface thereof. In any event, one or more straps, suchas webbing straps or cordlash 144 (FIG. 7F), may be configured tocircumferentially wrap around the blade 40 and at least a portion of theupper cradle 130 and/or lower turntable 100 to secure the blade 40against the saddles 138 and to counteract any vertical accelerationforces acting on the blade 40.

The illustrated upper cradle 130 includes a pair of oppositely disposedsupport bores 146 positioned on outer side surfaces of the frame 132 andconfigured for axial alignment with the support heels 118 of the lowerturntable 100 and for receiving respective support pins 148therethrough, such that the upper cradle 130 may be mounted to the lowerturntable 100 via the support pins 148, support bores 146, and supportheels 118. In the embodiment shown, a threaded shank 150 extendsoutwardly from the respective outer side surface of the frame 132proximate each of the support bores 146, and each support pin 148includes a flange 152 having a curved slot 154 configured to receive therespective threaded shank 150 for limiting relative movement between theframe 132 and the support pin 148. In this regard, a nut 156 may beconfigured for threadable engagement with each threaded shank 150 tosandwich the flange 152 of the respective support pin 148 between thenut 156 and the frame 132, and a padlock 158 may be inserted through aradial bore (not shown) at or near an outer end of the threaded shank150 for preventing the nut from becoming inadvertently dislodged fromthe threaded shank 150.

In the embodiment shown, the upper cradle 130 also includes a first pairof upper eyelets 160 positioned on a central side surface of the frame132 and a second pair of upper eyelets 162 (FIG. 5B) positioned on anopposite central side surface of the frame 132. A first threaded shank164 extends outwardly from the outer side surface of at least one of thefirst pair of upper eyelets 160 and a second threaded shank 166 extendsoutwardly from the outer side surface of at least one of the second pairof upper eyelets 162.

As best shown in FIG. 5B, the second pair of upper eyelets 162 areconfigured for vertical alignment with the pair of lower eyelets 120 onthe lower turntable 100. In this regard, an angle plate 170 having upperand lower bores 172, 174 may be selectively positioned between the pairof lower eyelets 120 and the second pair of upper eyelets 162 such thatthe upper and lower bores 172, 174 are axially aligned therewith forreceiving respective locking pins 176 therethrough. In this manner, theorientation of the upper cradle 130 relative to the lower turntable 100about a first horizontal axis H1 collectively defined by the supportpins 148, support bores 146, and support heels 118, may be selectivelyand/or variably fixed. In one embodiment, a variety of angle plates 170having upper and lower bores 172, 174 spaced apart from each other byvarious different distances may be provided, so that a particular angleplate 170 may be selected to provide a particular desired fixedorientation of the upper cradle 130 relative to the lower turntable 100.For example, a particular angle plate 170 may correspond to the desiredfixed orientation of the upper cradle 130 relative to the lowerturntable 100 for accommodating a particular shape or configuration ofthe blade 40. In the embodiment shown, each locking pin 176 includes anflange 180 having a curved slot 182 configured to receive the respectivethreaded shank 122, 166 for limiting relative movement between therespective frame 102, 132 and respective locking pin 176. In thisregard, a nut 184 may be configured for threadable engagement with eachthreaded shank 122, 166 to sandwich the flange 180 of the respectivelocking pin 176 between the nut 184 and the respective eyelet 120, 162.The illustrated upper cradle 130 also includes a plurality of hoistrings 190 positioned on an upper surface of the frame 132 and configuredto facilitate hoisting of the upper cradle 130 onto the lower turntable100 via a lifting arrangement (not shown), for example.

As best shown in FIG. 5C, the illustrated root bolster 30 furtherincludes a rigid arm 200 hingedly coupled to the upper cradle 130 abouta second horizontal axis H2 and configured to extend from the uppercradle 130 toward the root end 42 of the blade 40 carried by the rootbolster 30. The rigid arm 200 may be fixed against rotation relative tothe lower turntable 100 and upper cradle 130 about the first verticalaxis V1 such that the rigid arm 200, upper cradle 130, and lowerturntable 100 may rotate thereabout together, and the rigid arm 200 mayfurther be selectively fixed against rotation relative to the uppercradle 130 about the second horizontal axis H2.

As shown, the rigid arm 200 includes a generally cylindrical body 202extending between a proximal end 204 coupled to the upper cradle 130 anda distal end 206 configured to be selectively rigidly coupled to theroot end 42 of the blade 40. In one embodiment, the length of the body202 of the rigid arm 200 may be equal to the first distance D1 betweenthe root end 42 of the blade 40 to be supported by the root bolster 30and the first vertical axis V1. Thus, the length of the body 202 may beapproximately one-tenth of the length L of the blade 40. For example,the length of the body 200 may be between approximately 20 feet (approx.6 m) and approximately 40 feet (approx. 12 m), such as approximately 23feet (approx. 7 m).

In the embodiment shown, the rigid arm 200 includes a proximal eyelet210 positioned at or near the proximal end 204 of the cylindrical body202 and a distal eyelet 212 positioned at or near the distal end 206 ofthe cylindrical body 202. The proximal eyelet 210 is configured foraxial alignment with the first pair of upper eyelets 160 of the uppercradle 130 and for receiving a pivot pin 214 therethrough, such that thepivot pin 214, proximal eyelet 210, and first pair of upper eyelets 160may collectively define the second horizontal axis H2. In the embodimentshown, the pivot pin 214 includes a flange 216 having a curved slot 218configured to receive the threaded shank 164 for limiting relativemovement between the frame 132 and the pivot pin 214. In this regard, anut 220 may be configured for threadable engagement with the threadedshank 164 to sandwich the flange 216 of the pivot pin 214 between thenut 220 and the eyelet 160.

In one embodiment, a lock (not shown) may selectively fix the rigid arm200 against rotation relative to the upper cradle 130 about the secondhorizontal axis H2. As described in greater detail below, the distaleyelet 212 is configured to selectively receive a locking pin 222 forrigidly coupling the root end 42 of the blade 40 to the distal end 206of the rigid arm 200. In the embodiment shown, a threaded shank 224extends outwardly from an upper surface of the distal eyelet 212, andthe locking pin 222 includes a flange 226 having a curved slot 228configured to receive the threaded shank 224 for limiting relativemovement between the body 202 of the rigid arm 200 and the locking pin222. In this regard, a nut 230 may be configured for threadableengagement with the threaded shank 224 to sandwich the flange 226 of thelocking pin 222 between the nut 230 and the distal eyelet 212.

Thus, the rigid arm 200 may be selectively rotatable about the secondhorizontal axis H2, for example, between a stowed position (FIG. 7A) andat least one deployed position (FIGS. 7B and 7C). When in the stowedposition, the body 202 of the rigid arm 200 may be oriented about secondhorizontal axis H2 to slope downwardly from the proximal end 204 at theupper cradle 130 toward the distal end 206 at or near the bed 16 of therailcar 14. For example, the distal end 206 of the rigid arm 200 mayrest on or near the bed 16 of the railcar 14 when in the stowedposition. When in the deployed position, the body 202 of the rigid arm200 may be oriented about the second horizontal axis H2 to be generallyhorizontal, or to slope upwardly from the proximal end 204 toward thedistal end 206, or to slope downwardly from the proximal end 204 towardthe distal end 206 less steeply than when in the stowed position. Forexample, the distal end 206 of the rigid arm 200 may be slightly above,slightly below, or generally level with the proximal end 204 of therigid arm 200, and may be supported above the bed 16 of the railcar 14,when in a deployed position. In one embodiment, the body 202 of therigid arm 200 may be cantilevered over the bed 16 of the railcar 14 fromthe proximal end 204 of the rigid arm 200 by selectively fixing therigid arm 200 against rotation relative to the upper cradle 130 aboutthe second horizontal axis H2 when in a deployed position. In anotherembodiment, the body 202 of the rigid arm 200 may be supported above thebed 16 of the railcar 14 at or near both the proximal and distal ends204, 206, such as via the upper cradle 130 at the proximal end 204 andvia a temporary support structure positioned below the distal end 206,when in a deployed position.

In this regard, the illustrated root bolster 30 also includes anarticulating leg 240 hingedly coupled to the body 202 of the rigid arm200 at or near the distal end 206 thereof and, more particularly, at ajoint 242 defining a third horizontal axis H3 such that the articulatingleg 240 is rotatable relative to the rigid arm 200 about the thirdhorizontal axis H3 between a retracted position (FIG. 7A) in which thearticulating leg 240 is longitudinally aligned with and tucked againstthe rigid arm 200, and at least one extended position (FIGS. 7B and 7C)in which the articulating leg 240 extends generally downwardly from therigid arm 200 toward the bed 16 of the railcar 14. The illustratedarticulating leg 240 includes a pair of wheels 244 located opposite thejoint 242 for movably supporting the articulating leg 240 on the bed 16of the railcar 14. In the embodiment shown, a laterally-extendingbarrier 246 (FIG. 5 ) is provided on the bed 16 of the railcar 14 and isspaced apart from the root fixture 70 for selectively abutting thewheels 244 of the articulating leg 240 to assist in maintaining thearticulating leg 240 in an extended position, as described in greaterdetail below. In one embodiment, the barrier 246 may be welded to thebed 16 of the railcar 14 to fixedly couple the barrier 246 to the bed 16of the railcar 14. Alternatively, the barrier 246 may be fixedly coupledto the bed 16 of the railcar 14 in any other suitable manner. Theillustrated articulating leg 240 also includes at least one spring 250between the wheels 244 and the joint 242 for absorbing and damping shockimpulses, for example.

While not shown, a locking mechanism may be configured to selectivelylock the articulating leg 240 in at least the retracted position. Forexample, such a locking mechanism may include a pair of magnets, one ofwhich is fixedly coupled to the articulating leg 240 at a positionspaced apart from the joint 242 and the other of which is fixedlycoupled to the body 202 of the rigid arm 200 for magnetic engagementtherebetween when the articulating leg 240 is in or near the retractedposition. The magnetic attraction between the magnets may be sufficientto securely retain the articulating leg 240 in the retracted position.In the embodiment shown, an on/off lever 252 (FIG. 7A) is configured tobe movable between an “off” position in which the lever 252 causes ashield (not shown) to cover at least one of the magnets therebyinterrupting the magnetic attraction between the magnets, and an “on”position in which the lever causes the shield to uncover the at leastone of the magnets. Thus, the articulating leg 240 may be secured in theretracted position when the magnets are magnetically engaged with thelever 252 in the “on” position, and may be moved away from the retractedposition toward the at least one extended position when the magnets aremagnetically disengaged with the lever 252 in the “off” position. Itwill be appreciated that the locking mechanism may be configured in anyother suitable manner for selectively locking the articulating leg 240in at least the retracted position.

In one embodiment, the distal end 206 of the rigid arm 200 is configuredto be rigidly coupled to the root end 42 of the blade 40 when the rigidarm 200 is in the deployed position. For example, the distal end 206 ofthe rigid arm 200 may be configured to be initially rigidly coupled tothe root end 42 of the blade 40 when the rigid arm 200 is in thedeployed position and when the distal end 206 of the rigid arm 200 issupported above the bed 16 of the railcar 14 by the extendedarticulating leg 240, and may be configured to remain rigidly coupled tothe root end 42 of the blade 40 when the articulating leg 240 issubsequently moved to the retracted position, as described in greaterdetail below.

In this manner, the rigid arm 200 may be capable of providing a linkagebetween the root end 42 of the blade 40 and the upper cradle 130 of theroot bolster 30 and may thereby assist in transmitting longitudinalacceleration and/or deceleration forces between the root end 42 of theblade 40 and the root fixture 70. By rotating about the first verticalaxis V1 along with the upper cradle 130 and lower turntable 100 of theroot bolster 30, the rigid arm 200 may remain longitudinally alignedwith the blade 40 and may assist in allowing the root end 42 of theblade 40 to swing out over and beyond the edge of the railcar 14, suchas while rounding a curved section of the railroad. In this regard, theblade 40 may be rested on the saddles 138 of the root bolster 30 at aposition inboard of the root end 42 by approximately the same length asthe length of the rigid arm 200, and may be rigidly coupled to thedistal end 206 of the rigid arm 200 at the root end 42, as described ingreater detail below.

Referring now primarily to FIGS. 6-6B, the illustrated tip bolster 32 ismovably mounted to a tip fixture 260 fixedly coupled to the bed 16 ofthe underlying railcar 14 against movement relative thereto. As shown,the tip fixture 260 includes a pair of longitudinally extending rails262 spaced apart from and rigidly coupled to each other by a pluralityof laterally extending ties 264 and corresponding brackets 266. In theembodiment shown, the rails 262 each extend along the bed 16 of therailcar 14 between first and second ends 270, 272, and are elevatedabove the bed 16 of the railcar 14 by the brackets 266. As shown in FIG.6A, a through-bore 274 is positioned at or near each of the ends 270,272 of the rails 262 and a laterally-inwardly extending stopper 276 isaligned therewith and removably coupled to the respective rail 262 via acorresponding fastener 278 extending therethrough for limitingtranslational movement of the tip bolster 32 along the rails 262, asdescribed in greater detail below. In one embodiment, the tip fixture260 may be welded to the bed 16 of the railcar 14 along the edges of theties 264 to fixedly couple the tip fixture 260 to the bed 16 of therailcar 14. Alternatively, the tip fixture 260 may be fixedly coupled tothe bed 16 of the railcar 14 in any other suitable manner. Theillustrated tip fixture 260 also includes a plurality of hoist grommets280 (FIG. 6 ) positioned on outer side surfaces of the rails 262 andconfigured to facilitate hoisting of the tip fixture 260 onto the bed 16of the railcar 14 via a lifting arrangement (not shown), for example.

As best shown in FIGS. 6A and 6B, the illustrated tip bolster 32includes a lower carriage 300 configured to be mounted to the tipfixture 260 and longitudinally translatable relative thereto along therails 262. In the embodiment shown, the lower carriage 300 includes achassis 302 carrying a platform 304, and a central shaft 306 extendinggenerally upwardly from the platform 304. As shown, the chassis 302 hasa pair of longitudinally extending sidewalls 310 spaced apart from andrigidly coupled to each other by a pair of laterally extending crosssupports 312. Each of the sidewalls 310 includes a pair oflaterally-outwardly extending lower rollers 314 and a corresponding pairof laterally-outwardly extending upper sliders 316 vertically alignedtherewith, such that each set of vertically-aligned rollers 314 andsliders 316 may be configured to capture a respective one of the rails262 therebetween for translatably securing the lower carriage 300, andthus the tip bolster 32, to the tip fixture 260. In the embodimentshown, a laterally-outwardly extending bumper 318 is positioned betweeneach set of vertically-aligned rollers 314 and sliders 316 and isconfigured to selectively abut the respective stopper 276 of thecorresponding rail 262 to limit translational movement of the tipbolster 32 along the rails 262 between the first and second ends 270,272 thereof and thereby prevent the tip bolster 32 from becominginadvertently dislodged from the tip fixture 260. The stoppers 276 maybe selectively removable from the respective rails 262 for allowinginitial mounting of the lower carriage 300 to the tip fixture 260, asindicated by the arrows A1 in FIG. 6A, or subsequent dismounting of thelower carriage 300 from the tip fixture 260.

In the embodiment shown, the platform 304 has a pair of lateralgenerally circular arc-shaped peripheral portions 320 and a generallyI-shaped central portion 322 for providing rigidity to the platform 304and from which the central shaft 306 extends. The generally circulararc-shaped peripheral portions 320 define respective upper bearingsurfaces 324, the purpose of which is described below. In the embodimentshown, the shaft 306 includes a central bore 326 for rotatably receivinga generally cylindrical spindle 328. As shown, the spindle 328 includesa plurality of threaded bores 330 for threadably receiving respectivefasteners 332 (FIG. 6B). The lower carriage 300 may also include aplurality of hoist rings (not shown) positioned on the outer sidesurfaces of the generally arc-shaped peripheral portions 320 andconfigured to facilitate hoisting of the lower carriage 300 onto the tipfixture 260 via a lifting arrangement (not shown), for example.

The illustrated tip bolster 32 also includes an intermediate turntable340 pivotably coupled to the lower carriage 300 about the secondvertical axis V2 and fixed against linear movement relative to the lowercarriage 300, such that the intermediate turntable 340 and lowercarriage 300 are configured to translate along the rails 262 together.In the embodiment shown, the intermediate turntable 340 has a generallyI-shaped frame 342 and may include a central bore (not shown) on a lowerside thereof configured to rotatably receive the shaft 306 of the lowercarriage 300 such that the bore and the shaft 306 may collectivelydefine the second vertical axis V2. As best shown in FIG. 6B, theintermediate turntable 340 includes a central raised boss 344 extendingupwardly from the frame 342 and including a plurality of through-bores346 configured for axial alignment with the threaded bores 330 of therotatable spindle 328 of the lower carriage 300 and for receiving therespective fasteners 332 therethrough to secure the intermediateturntable 340 to the rotatable spindle 328. In the embodiment shown, theintermediate turntable 340 also includes a plurality of peripheral feet348 extending generally downwardly from the frame 342 and each having alower bearing surface 350 configured to glide along the respectivecircular arc-shaped bearing surface 324 of the lower carriage 300 duringrotation of the intermediate turntable 340 relative thereto to assist insupporting the intermediate turntable 340 on the lower carriage 300. Theillustrated intermediate turntable 340 also includes a pair of flanges352 extending generally upwardly from the frame 342 and spaced apartfrom each other to define a channel 354 therebetween. As shown, eachflange 352 includes a plurality of holes 356 arranged such that eachhole 356 in one of the flanges 352 is axially aligned with acorresponding hole 356 in the other of the flanges 352. The illustratedintermediate turntable 340 also includes a plurality of hoist rings 358positioned on an upper surface of the frame 342 and configured tofacilitate hoisting of the intermediate turntable 340 onto the lowercarriage 300 via a lifting arrangement (not shown), for example.

In the embodiment shown, the tip bolster 32 also includes an upper clamp360 selectively fixed against movement relative to the intermediateturntable 340 such that the upper clamp 360 and intermediate turntable340 are configured to rotate together about the second vertical axis V2,and such that the upper clamp 360, intermediate turntable 340, and lowercarriage 300 are configured to translate together along the rails 262.As shown, the upper clamp 360 includes a clamp frame 362, as well asfirst and second clamp arms 364, 366 selectively movable relative toeach other in a clamping direction. In the embodiment shown, the firstclamp arm 364 is configured to be stationary relative to the clamp frame362, and the second clamp arm 366 is configured to be movable relativeto the clamp frame 362 toward and away from the first clamp arm 364 inthe clamping direction. In this regard, the illustrated first clamp arm364 is integrally formed together with the clamp frame 362 as a unitarypiece. The illustrated clamp frame 362 is sized and configured to bepartially received within the channel 354 of the intermediate turntable340, and includes a pair of lower bores 368 configured for axialalignment with a selected set of holes 356 in the flanges 352 of theintermediate turntable 340 and for receiving respective locking rods 370therethrough. In this manner, the position of the clamp frame 362relative to the intermediate turntable 340 may be selectively fixed. Thevarious sets of holes 356 in the flanges 352 available for alignmentwith the lower bores 368 of the clamp frame 362 may allow the particularposition of the clamp frame 362 within the channel 354 to be adjusted asdesired. In the embodiment shown, each locking rod 370 includes a flange372 at or near one end thereof and a radial bore 374 for receiving athreaded fastener 376 at or near the other end thereof, the threadedfastener 376 being configured to threadably engage a nut 378 forselectively capturing the flanges 352 of the intermediate turntable 340between the flange 372 of the locking rod 370 and the fastener 376 andaccompanying nut 378. The illustrated upper clamp 360 also includes aplurality of hoist rings 380 positioned on upper surfaces of the clamparms 364, 366 and configured to facilitate hoisting of the upper clamp360 onto the intermediate turntable 340 via a lifting arrangement (notshown), for example.

The illustrated upper clamp 360 has upper pivot blocks 382 (FIG. 8A)extending generally inwardly from each of the clamp arms 364, 366. Asshown, each of the pivot blocks 382 pivotably supports at least onerespective jaw 384, 386 configured to confront the pressure side 50 orthe suction side 52 of the blade 40 at or near the leading edge 46 ofthe blade 40, and further pivotably supports at least one respectivesaddle arm 388. Since the first clamp arm 364 is configured to bestationary relative to the clamp frame 362 and the second clamp arm 366is configured to be movable relative to the clamp frame 362, the jaw 384of the first clamp arm 364 may be considered “stationary” and the jaw386 of the second clamp arm 366 may be considered “movable”. In anyevent, each of the jaws 384, 386 includes at least one friction pad 390configured to frictionally engage the respective side 50, 52 of theblade 40. In this regard, the jaws 384, 386 and/or friction pads 390 maybe sized and shaped to conform to the exterior surface of the blade 40.In one embodiment, the friction pads 390 may include a rubber material.In the embodiment shown, each of the saddle arms 388 carries arespective saddle bar 392, and a pliable saddle 394 configured toconfront the leading edge 46 of the blade 40 extends loosely between thesaddle bars 392 of the first and second clamp arms 364, 366. In thisregard, the pliable saddle 394 may be configured as an endless loop ofmaterial wrapped about the saddle bars 392. In one embodiment, eachsaddle arm 388 and accompanying saddle bar 392 may be rigidly coupled tothe respective jaw 384, 386 so as to pivot relative to the correspondingclamp arm 364, 366 therewith. In this manner, the pliable saddle 394 maybe configured to allow the blade 40 to rotate slightly about thelongitudinal axis of the blade 40 to mechanical equilibrium (which mayinclude leaning against one of the jaws 384, 386, for example) as theweight of the blade 40 is transferred to the pliable saddle 394 duringlowering of the blade 40 onto the tip bolster 32, and may further beconfigured to tilt one or both of the jaws 384, 386 toward the exteriorsurface of the blade 40 during such lowering of the blade 40. Thus, thepliable saddle 394 may provide some flexibility to the positioning ofthe blade 40 between the jaws 384, 386. The pivotability of the jaws384, 386 relative to the pivot blocks 382 and the pliability of thesaddle 394 may allow the jaws 384, 386 and/or saddle 394 toautomatically adjust under the weight of the blade 40 to conform to theexterior surface thereof.

In the embodiment shown, the upper clamp 360 further includes a pair ofperipheral guide rods 400 extending parallel to the clamping directionand fixedly coupled to the clamp frame 362 against movement relativethereto. The second clamp arm 366 includes two corresponding pairs oflower notches 402 configured to slidably receive the pair of guide rods400 such that the second clamp arm 366 may be movable toward (e.g.,forward) and away from (e.g., backward) the first clamp arm 364 alongthe pair of guide rods 400 for moving the movable jaw 386 toward andaway from the stationary jaw 384 to apply and release a clamping forceto/from the blade 40 interposed therebetween and resting on the saddle394. For example, the movable jaw 386 may be moved into contact with theblade 40 to press the blade 40 against the stationary jaw 384 forgenerating such a clamping force.

The illustrated upper clamp 360 also includes an actuator 410 configuredto effect forward and backward movement of the second clamp arm 366along the pair of guide rods 400. As shown, the actuator 410 includes arotatable drive screw 412 extending parallel to the clamping direction,horizontally aligned with and equally spaced between the pair of guiderods 400, and fixed against movement relative to the clamp frame 362parallel to the clamping direction. In this regard, the drive screw 412is rotatably supported by a first end plate 414 fixedly coupled directlyto the clamp frame 362 generally between the first and second clamp arms364, 366, and by a second end plate 416 fixedly coupled to the clampframe 362 via the pair of guide rods 400 on a side of the second clamparm 366 generally opposite from the first clamp arm 364. The actuator410 further includes a drive plate 418 having a pair of outerthrough-bores 420 configured to slidably receive the pair of guide rods400 such that the drive plate 418 may be movable along the pair of guiderods 400. As shown, the drive plate 418 also includes a central threadedbore 422 configured to threadably receive the drive screw 412, such thatrotation of the drive screw 412 may effect forward or backward movementof the drive plate 418 along the guide rods 400. For example, clockwiserotation of the drive screw 412 may effect forward movement of the driveplate 418 along the guide rods 400 to urge the second clamp arm 366forward for applying a clamping force to the blade 40 via the jaws 384,386, while counterclockwise rotation of the drive screw 412 may effectbackward movement of the drive plate 418 along the guide rods 400 toallow the second clamp arm 366 to be moved backward for releasing theblade 40 from the jaws 384, 386. The drive plate 418 may be selectivelyfixed at a particular location along the guide rods 400 when the drivescrew 412 is rotationally stationary, such as when a desired clampingforce on the blade 40 has been achieved, as described in greater detailbelow. In one embodiment, the drive screw 412 may be operatively coupledto a motor (not shown) for automatically rotating the drive screw 412 inthe clockwise and/or counterclockwise direction.

In the embodiment shown, the actuator 410 further includes a mechanicalenergy storage device shown here in the form of a pair of coil springs430 (FIGS. 8A and 9A) although other devices may be contemplated, suchas leaf springs or belleville springs or piston type devices. These maybe positioned between the drive plate 418 and the second clamp arm 366and configured to selectively store and release energy between the driveplate 418 and the second clamp arm 366, thereby providing someflexibility to the actuator 410. In the illustrated example, coilsprings 430 are shown arranged about the pair of guide rods 400. Thismechanical energy storage device allows the clamp 360 to respond tounexpected decreases in the clamping force being applied to the blade40. In this regard, the illustrated springs 430 are each configured totransmit the forward linear movement of the drive plate 418 along theguide rods 400 to the second clamp arm 366 for urging the second clamparm 366 forward until the movable jaw 386 presses the blade 40 againstthe stationary jaw 384 and further forward movement of the second clamparm 366 is generally resisted by the blade 40. The springs 430 are eachfurther configured to be compressed or “pre-loaded” by the drive plate418 as the drive plate 418 continues to move forward along the guiderods 400 after the movable jaw 386 presses the blade 40 against thestationary jaw 384. In this manner, the mechanical energy storage device(e.g. springs 430) may assist in preventing such continued forwardmovement of the drive plate 418 from further urging the second clamp arm366 forward which could otherwise result in an excessive, potentiallydamaging clamping force being applied to the blade 40. Moreover, themechanical energy storage device—e.g. comprising or including compressedor pre-loaded springs 430—may be capable of expanding in response to anunexpected positional shift of the blade, causing a decrease or loss ofcontact between the movable jaw 386 and the blade 40. Such a decrease orloss of contact may in particular be characterised as a momentarydecrease in the clamping force. A decrease in the clamping force may inparticular arise as a result of a shift in position of the clampedelement, i.e. a shift in position of the blade 40, perhaps as a resultof a large jolt during transportation. In response to such a jolt, ablade 40 may slightly shift its position, and may thereafter present anarrower profile between the clamp jaws 384, 386. In the presentspecification, a decrease in the clamping force may be alternatively beunderstood or expressed as a shift in position of the clamped blade.Expansion of the springs 430 under these circumstances may urge thesecond clamp arm 366 further forward to cause the movable jaw 386 toadvance toward the stationary jaw 384 and thereby increase the contactand/or the clamping force applied to the blade 40. In this manner, thesprings 430 may automatically compensate for undesirable decreases orlosses of contact between the jaws 384, 386 and the blade 40, which maybe indicative of the blade 40 creeping, drifting, or otherwise beginningto slip. The mechanical energy storage device ensures that the clampingforce applied to the blade 40 between the jaws 384, 386, e.g. duringinitial securement of the blade 40 in the tip bolster 32 or during aninitial stage of a transport operation, is maintained substantiallyconstant, even after a shift in position of the blade 40. This ensuresthat a decrease or loss of contact between the movable jaw 386 and theblade 40 is only momentary and therefore benign. Thus, the springs 430may assist in maintaining a substantially continuous desired clampingforce on the blade 40.

In one embodiment, the drive screw 412 may be configured to effectforward linear movement of the drive plate 418 until a desired amount ofclamping force is applied by the jaws 384, 386 to the blade 40, and/oruntil a desired amount of compression or pre-loading of the springs 430has been achieved. In this regard, the amount of compression of thesprings 430 and the amount of clamping force applied to the blade 40each correspond to the distance between the drive plate 418 and thesecond clamp arm 366. Thus, the drive screw 412 may be configured toposition the drive plate 418 at a particular location along the guiderods 400 corresponding to the desired amount of clamping force and/orpre-loading. In one embodiment, the guide rods 400 may include indicia(not shown) for providing a visual indication of such a particularlocation to an operator of the tip bolster 32 or other personnel.

While the energy storage devices of this embodiment are illustrated as apair of coil springs 430, any other suitable energy storage devices,such as one or more hydraulic accumulators, may be used to selectivelystore and release energy between the drive plate 418 and the secondclamp arm 366 in response to the applied clamping force falling belowthe desired amount.

In the embodiment shown, the upper clamp 360 further includes a pair ofspring-loaded separators 440 extending between the first and secondclamp arms 364, 366 for biasing the second clamp arm 366 away from thefirst clamp arm 364 in the clamping direction. Each of the illustratedspring-loaded separators 440 is telescopic and includes at least oneouter tuber 442 and at least one inner tube 444 biased axially away fromeach other by an internal biasing member, such as a coil spring or ahydraulic accumulator (not shown), for example, as well as a protectivegasket 446 positioned about the interface between the outer and innertubes 442, 444 for preventing dirt or other debris from collectingtherebetween. The spring-loaded separators 440 may be configured to urgethe second clamp arm 366 backward for releasing the blade 40 from thejaws 384, 386, such as when the drive screw 412 is rotated to move thedrive plate 418 backward along the guide rods 400 allowing the springs430 to expand in a backward direction and thereby remove any forceapplied to the second clamp arm 366 by the springs 430. In this manner,the spring-loaded separators 440 may automatically cause the blade 40 tobe released from the jaws 384, 386 when the force applied to the secondclamp arm 366 by the springs 430 is removed by retracting the driveplate 418 backward along the guide rods 400, without requiringintervention of an operator or other personnel to push the second clamparm 366 backward.

Thus, the upper clamp 360 may be capable of applying a substantiallycontinuous clamping force to the blade 40 and may thereby assist intransmitting longitudinal acceleration and/or deceleration forcesbetween the tip region 64 of the blade 40 and the tip fixture 260, aswell as counteracting any vertical acceleration forces acting on theblade 40. By being longitudinally translatable along the rails 262, thelower carriage 300 may compensate for changes in the profile of thetrain 12, such as while rounding a curved section of the railroad.

Referring now to FIGS. 7A-7F, a method of loading the blade 40 onto theroot bolster 30 is provided. Initially, the rigid arm 200 of the rootbolster 30 may be resting on or near the bed 16 of the railcar 14 in thestowed position, and the articulating leg 240 may be in the retractedposition. A first lifting arrangement 450 including a hoist rope 452, ahook 454, and a sling 456 may be operatively attached to the body 202 ofthe rigid arm 200, and the rigid arm 200 may thereby be lifted upwardlyand rotated about the second horizontal axis H2, for example, from thestowed position to a deployed position, as indicated by the arrow A2 inFIG. 7A. After the rigid arm 200 has been lifted away from the stowedposition, the locking mechanism for the articulating leg 240 may bedisengaged, such as by moving the lever 252 to the “off” position, andthe articulating leg 240 may be rotated about the third horizontal axisH3 from the retracted position toward an extended position, as indicatedby the arrow A3 in FIG. 7B. The distal end 206 of the rigid arm 200 maythen be lowered downwardly toward the bed 16 of the railcar 14 by thefirst lifting arrangement 450, as indicated by the arrow A4 in FIG. 7C,to allow the wheels 244 of the articulating leg 240 to rest on the bed16 of the railcar 14. The first lifting arrangement 450 may then beremoved from the rigid arm 200. As shown in FIG. 7C, the wheels 244 ofthe articulating leg 240 may be rolled into abutment with the barrier246 on the bed 16 of the railcar 14 on a side of the barrier 246opposite from the root fixture 70 to temporarily secure the rigid arm200 in the illustrated deployed position.

With the rigid arm 200 secured in place, the blade 40 may be liftedabove and longitudinally aligned with the root bolster 30 with theleading edge 46 of the blade 40 facing downwardly by at least one secondlifting arrangement 460 including a hoist rope 462, a sheave 464, adouble hook 466, and a lifting cable 468 operatively attached to theroot frame 56, as shown in FIG. 7D. While not shown, a third liftingarrangement may be operatively attached to the tip frame 58, such as forcoordinated lifting of the entire blade 40. The blade 40 may then beadvanced generally horizontally by the second lifting arrangement 460 tofacilitate rigidly coupling the root frame 56 of the blade 40 to thedistal end 206 of the rigid arm 200, such as via the distal eyelet 212and locking pin 222, as indicated by the arrow A5 in FIG. 7D. With theroot frame 56 rigidly coupled to the distal end 206 of the rigid arm200, thereby providing a linkage between the root end 42 of the blade 40and the upper cradle 130 of the root bolster 30, the root end 42 of theblade 40 may be lifted slightly upwardly, as indicated by the arrow A6in FIG. 7E, to allow the articulating leg 240 to be rotated over thebarrier 246 and returned to the retracted position, as indicated by thearrow A7 in FIG. 7E. In one embodiment, the locking mechanism for thearticulating leg 240 may be re-engaged, such as by moving the lever 252to the “on” position, to secure the articulating leg 240 in theretracted position. The root end 42 of the blade 40 may then be lowereddownwardly toward the bed 16 of the railcar 14, as indicated by thearrows A8 in FIG. 7F, to allow the portions of the pressure side 50 andsuction side 52 at or near the leading edge 46 of the blade 40 to reston the saddles 138 of the root bolster 30 at a position inboard of theroot end 42 by approximately the same length as the length of the rigidarm 200. In one embodiment, the angle plate 170 may be secured in placeprior to such lowering of the blade 40 in order to selectively fix adesired orientation of the upper cradle 130 relative to the lowerturntable 100 about the first horizontal axis H1 for accommodating aparticular shape or configuration of the blade 40. As described above,the saddles 138 may automatically adjust under the weight of the blade40 to conform to the exterior surface thereof. The webbing straps orcordlash 144 may then be circumferentially wrapped around the blade 40and at least a portion of the upper cradle 130 and/or lower turntable100, such as the saddles 138 of the upper cradle 130.

With the blade 40 loaded onto the root bolster 30 as described above,the second lifting arrangement 460 may be selectively detached from theroot frame 56. During subsequent transportation of the blade 40 via thetrain 12, longitudinal acceleration and/or deceleration forces aretransmitted between the root end 42 of the blade 40 and the root fixture70 via the rigid arm 200, while the saddles 138 primarily verticallysupport the blade 40 and the webbing straps or cordlash 144 primarilycounteract any vertical acceleration forces acting on the blade 40. Theentire blade 40, including the root end 42 thereof, rotates about thefirst vertical axis V1 along with the upper cradle 130, lower turntable100, and rigid arm 200 of the root bolster 30 while rounding a curvedsection of the railroad thereby allowing the root end 42 of the blade 40to swing out over and beyond the edge of the railcar 14 to efficientlyutilize the available side clearances along the railroad. After thetrain 12 has reached the desired destination, the webbing straps orcordlash 144 may be unwrapped and the root frame 56 may be uncoupledfrom the rigid arm 200 of the root bolster 30 for removal of the blade40 from the root bolster 30.

Referring now to FIGS. 8A-8E and 9A-9C, a method of loading the blade 40onto the tip bolster 32 is provided. Initially, the second clamp arm 366is spaced sufficiently far apart from the first clamp arm 364 to allowpassage of the tip region 64 of the blade 40 between the jaws 384, 386,as shown in FIG. 8A. The tip region 64 of the blade 40 is then loweredtoward the bed 16 of the railcar 14 with the leading edge 46 of theblade 40 facing downwardly to allow the leading edge 46 of the blade 40to contact the pliable saddle 394, as shown in FIG. 8B, such as via athird lifting arrangement (not shown) operatively attached to the tipframe 58. In one embodiment, such lowering of the tip region 64 of theblade 40 may be performed concurrently with the lowering of the root end42 of the blade 40 described above with respect to FIG. 7F. In anyevent, as the weight of the blade 40 is transferred to the pliablesaddle 394, the blade 40 may rotate slightly about the longitudinal axisof the blade 40 to lean against the stationary jaw 384, and the pliablesaddle 394 may tilt at least the movable jaw 386 toward the exteriorsurface of the blade 40, as shown in FIGS. 8C and 9A. The second clamparm 366 may then be urged forward along the guide rods 400 to move themovable jaw 386 into contact with the blade 40 to press the blade 40against the stationary jaw 384 for generating a desired clamping force,such as by operation of the actuator 410 including the drive screw 412,drive plate 418, and springs 430, as shown in FIGS. 8D and 9B. Asdescribed above, the jaws 384, 386 and/or saddle 394 may automaticallyadjust under the weight of the blade 40 to conform to the exteriorsurface thereof. The drive plate 418 may continue to move forward alongthe guide rods 400 after the desired clamping force has been generatedto thereby compress or pre-load the springs 430, as shown in FIGS. 8Eand 9C. After a desired amount of compression or pre-loading of thesprings 430 has been achieved, which may be indicated by the drive plate418 reaching a particular location along the guide rods 400, movement ofthe drive plate 418 may be halted and the drive plate 418 may beselectively fixed at the particular location along the guide rods 400 tomaintain the desired clamping force on the blade 40.

With the blade 40 loaded onto the tip bolster 32 as described above, thethird lifting arrangement may be selectively detached from the tip frame58. The tip frame 58 may remain coupled to the tip region 64 of theblade 40 or may be decoupled therefrom. During subsequent transportationof the blade 40 via the train 12, longitudinal acceleration and/ordeceleration forces are transmitted between the tip region 64 of theblade 40 and the tip fixture 260 via the upper clamp 360, which may alsocounteract any vertical acceleration forces acting on the blade 40, andthe springs 430 may counteract any longitudinal creeping or slipping ofthe blade 40 to maintain a substantially continuous clamping forcethereon, while the saddle 394 primarily vertically supports the blade40. The entire blade 40, including the tip end 44 thereof, rotates aboutthe second vertical axis V2 along with the upper clamp 360 andintermediate turntable 340 of the tip bolster 32 while rounding a curvedsection of the railroad thereby allowing the tip end 44 of the blade 40to swing out over and beyond the edge of the railcar 14 to efficientlyutilize the available side clearances along the railroad. During suchrotation, the blade 40 may also translate along the rails 262 togetherwith the upper clamp 360, intermediate turntable 340, and lower carriage300 of the tip bolster 32 to accommodate any resulting changes in theprofile of the train 12. After the train 12 has reached the desireddestination, the drive plate 418 may be moved backward along the guiderods 400 and the spring-loaded separators 440 may urge the second clamparm 336 backward to release the blade 40 from the jaws 384, 386 forremoval of the blade 40 from the tip bolster 32.

While the present invention has been illustrated by a description ofvarious preferred embodiments and while these embodiments have beendescribed in some detail, it is not the intention of the Applicant torestrict or in any way limit the scope of the appended claims to suchdetail. Additional advantages and modifications will readily appear tothose skilled in the art. The various features of the invention may beused alone or in numerous combinations depending on the needs andpreferences of the user.

What is claimed is:
 1. A tip bolster for supporting a wind turbine bladeon a railcar, the tip bolster comprising: a clamp including first andsecond clamp arms having first and second jaws, respectively, and beingconfigured to be selectively movable relative to each other in aclamping direction for applying and releasing a clamping force on theblade interposed therebetween, via the first and second jaws, whereinthe first and second clamp arms are configured to be urged relativelytoward each other in response to a decrease in the clamping force. 2.The tip bolster of claim 1, wherein the clamp further includes at leastone mechanical energy storage device configured to selectively store andrelease energy for urging at least one of the first and second clamparms relatively toward the other of the first and second clamp arms inresponse to the decrease in the clamping force.
 3. The tip bolster ofclaim 2, wherein the at least one mechanical energy storage deviceincludes at least one spring.
 4. The tip bolster of claim 1, wherein theclamp further includes at least one guide rod extending parallel to theclamping direction, and wherein the second clamp arm is movable towardand away from the first clamp arm along the at least one guide rod. 5.The tip bolster of claim 4, wherein the clamp further includes anactuator configured to effect movement of the second clamp arm along theat least one guide rod.
 6. The tip bolster of claim 5, wherein theactuator includes a rotatable drive screw extending parallel to theclamping direction and a drive plate including at least one through-boreconfigured to slidably receive the at least one guide rod and a threadedbore configured to threadably receive the drive screw, such thatrotation of the drive screw effects movement of the drive plate alongthe guide rods for urging the second clamp arm toward the first clamparm and for allowing the second clamp arm to be moved away from thefirst clamp arm.
 7. The tip bolster of claim 6, wherein the actuatorfurther includes at least one mechanical energy storage devicepositioned between the drive plate and the second clamp arm andconfigured to selectively store and release energy between the driveplate and the second clamp arm for urging the second clamp arm towardthe first clamp arm in response to the decrease in the clamping force.8. The tip bolster of claim 7, wherein the at least one mechanicalenergy storage device includes at least one spring.
 9. The tip bolsterof claim 8, wherein the at least one spring is positioned about the atleast one guide rod.
 10. The tip bolster of claim 8, wherein the atleast one spring is configured to be pre-loaded by the drive plate inresponse to continued movement of the drive plate toward the first clamparm after the second jaw presses the blade against the first jaw. 11.The tip bolster of claim 10, wherein the at least one spring isconfigured to expand in response to the decrease in the clamping forceto urge the second clamp arm toward the first clamp arm.
 12. The tipbolster of claim 1, wherein the clamp further includes at least onespring-loaded separator extending between the first and second clamparms for biasing the first and second clamp arms relatively away fromeach other in the clamping direction.
 13. The tip bolster of claim 1,further comprising: a turntable configured to be pivotable relative tothe railcar about a vertical axis, wherein the clamp is supported by theturntable.
 14. The tip bolster of claim 1, further comprising: acarriage configured to be translatable along the railcar in alongitudinal direction thereof, wherein the clamp is supported by thecarriage.
 15. A transportation arrangement comprising: the tip bolsterof claim 1 positioned on and pivotable relative to a first railcar abouta first vertical axis; a root bolster positioned on and pivotablerelative to a second railcar about a second vertical axis; and a bladepivotably supported on the first railcar via the tip bolster andpivotably supported on the second railcar via the root bolster.
 16. Amethod of transporting a wind turbine blade, comprising: providing arailcar and a tip bolster mounted to the railcar, wherein the tipbolster includes a clamp having first and second clamp arms having firstand second jaws, respectively; interposing the blade between the firstand second clamp arms; selectively moving the first and second clamparms relatively toward each other in a clamping direction for applying aclamping force on the blade via the first and second jaws; and urgingthe first and second clamp arms relatively toward each other in theclamping direction in response to a decrease in the clamping force. 17.The method of claim 16, wherein urging the first and second clamp armsrelatively toward each other includes selectively releasing energy fromat least one mechanical energy storage device to at least one of thefirst and second clamp arms in response to the decrease in the clampingforce.
 18. The method of claim 17, wherein the at least one mechanicalenergy storage device includes at least one spring.
 19. The method ofclaim 18, wherein selectively moving the first and second clamp armsrelatively toward each other includes pre-loading the at least onespring.
 20. The method of claim 16, further comprising: releasing theblade from the first and second jaws via at least one spring-loadedseparator extending between the first and second clamp arms for biasingthe first and second clamp arms relatively away from each other in theclamping direction.